Changing the engine control program

Discussion in 'Tech/Mech General' started by Douglas, Sep 13, 2009.

  1. Douglas


    Aug 22, 2008
    South Wales,
    I have often wondered when reading the claims made in the adverts for reprogramming the engine controls, why, if it is as good as the adverts claim do the manufacturers send the vehicles out with these changes already installed?

    Or could it be that these changes may damage the engine and the people selling the service don't give a dam; just so long as they get the money?

    Any body had this work done and found problems later?

  2. Kon tiki

    Kon tiki

    Oct 11, 2007
    North Wales
    A manufacturer would probably have an engine tuned within a specification that would be suitable for all engines allowing for some tolerance. I would think that the better companies who tweak the program do it for your particular vehicle on a rolling road to safely get the best out of it. Others who just reprogram the control without checking if its suitable for your induvidual vehicle are assuming that it will be ok for you & in some cases could possibly be over stressing some components.
    On the Renault Master they do offer it as a factory option of more power on the same engine, I don't know if it's anything more than just tweaking the computer but I can only guess that thereis a bit more to it than that. Even on mine which is the top engine at 146bhp I was told by one of these 'tuners' that he could give me another 10 to 15 horsepower :RollEyes: I think that for the van I have I have plenty of power without taking the chance.
  3. scotjimland

    scotjimland Funster Life Member

    Jul 25, 2007
    Suffolk Coastal
    Hi Doug

    Manufacturers have to take in to account the average van buyer, not every buyer wants maximum performance at the expense of fuel consumption.. so it's always going to be a compromise.

    If re-mapping is done by a reputable dealer it can improve power and drive-ability .. but anyone who claims it improves power AND MPG is dreaming .
    I would stay away from the eBay cowboys, anyone with half a brain can buy the software on discs and off they go..
    A reputable dealer will keep your original map on a hard drive and can return it to factory settings if so desired.

    I've done some Googling on engine damage and haven't found anything of note..


  4. Jaws

    Jaws Funster Life Member

    Sep 26, 2008
    had it done on the range rover ( diesel ), and it added 4mpg over a 6 week test period

    Had both the Smart cars remapped but for top end poke rather than economy ) and have done many thousands of miles on the remaps.. Very very happy so far .. And that is over a 6 year period :Smile:
  5. haganap

    haganap Funster Life Member

    Dec 5, 2007
    Cheshire- England
    I had my last van done with a considerable increase in both mpg and power. however the increase in MPG is outweighed by the ability to go faster therefore lowering MPG.

    There is not a great deal of risk of damage providing its done properly. So to answer your question as to why manufactureres dont send the vans/cars out with the extra upgrade. Well, they do. many cars for example are jazzed up with a few sportier goods and the engines BHP increased by using a different map.
    They are essentially the same engine.

    On to Vans/motorhomes. When a van comes out the manufacturers have to take in built in tollerances of all that drive them. White van man is not going to always adhere to service intervals etc. therefore tollorence is built in to allow this at a sacrifice of performance.

    secondly- strict eu guidelines on emmisions. they are tuned/mapped to be within these guidelines. however other countries that are outside the eu can and do have the same engines on a different map, with the same built in warranty.

    Thirdly, Manufacturers are not always responsible for building the maps. they often give engine blue prints out to other agencies to provide a map for that particular set up. Therefore there is often several available tht are not used and either sold on to other agencies whom eventually sell them on to Mr Ebay man or racing garage man depending on what you want. There are maps out thre that can tear a drive shaft out by merely producing enough power, I have seen this done on a Merc SLK .

    I do not proclaim to be an expert on the subject but done an awful lot of research prior to having my old van done. providing you increase oil and filter changes there is no danger.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice